Carburetor



July 26,I .1921.

F. G. CRNE cAr'zBUREToB Filled April 23, 1925 v 1 2 Sheets-Sheet 1 www mi WN,

NIN y ,l1 mu `Patented .luiy 25, 19E?.

FRANCIS G. CRQNE, OF BUFFALO, NEW YRK.

CARBURETOR.

Application filed April 23, 1925. Serial No. 25,255.

This invent-ion relates to a fuel preparing device or carburetor for gas engines and has as its principal object the provision ot' a device of this character in which air pre viously heated by the exhaust of the engines or otherwise is supplied to the mixture for increasing its power producing capacity and also to provide improved means for supplying a lean mixture where the engine is running at high speed and a rich mixture when running at low speed.

In the accompanying drawings:-

Fig. 1 is a vertical longitudinal sectionof a fuel mixing device or carburetor einbodying my invention.

Figure 21s a fragmentary horizontal section taken on line 2-2. Fig. 1.

Figure 3 is a vertical section ii-3, Fig. 1.

Figures 4 and 5 are fragmentary horizontal sections taken Von the correspondingly numbered lines in Fig. 1.

Figure 6 is a side elevation of a gas engine, on a reduced scale.y showing my improved fuel mixing device applied thereto.

Similar characters of reference indicate corresponding parts throughout the several. views.

The numeral 10 represents a gas engine ot well known construction having an intake 11 from which the explosive mixture is conducted to the working cylinder of the engine and an exhaust. or discharge conduit 12 through which the spent gases are carried away from the cylinder.

My improved fuel mixing .device com prises means for producing a mixture ofliqtaken on line uid fuel and air for running the engine at high speed, means for producing a mixture of liquid fuel and'air for running the engine at low speed and mea'ns for preheating the air for mixing the same with the fuel either when running at high or low speeds.

The general organization of the above described means comprises a main tubular or hollow body having a rear section 13 and a front section 14 which have their opposing ends detachably connected by screws 15. The interior of the rear section 13 forms an outlet or mixing chamber 16 which commu nicates with the fuel intake 11 ofthe engine to which the rear end of the rear .body section is connected by screws 17, and theinterior of the front section 14 forms an air chamber 18 which is provided at its `Jfront end with a laterally extending air inlet. 19

Vthrough which the external air is admitted directly to the carburetor. Vithin the rear part of the mixing chamber is arranged a throttle valve 20 preferably of the usual butterily type whereby the supply of combustible mixture .from the main vaporizing means to the engine is controlled, and .within the inlet 19 of the air chamber isA arranged a choke or air controllingvalve 21 of usual construction for controlling the direct supply ofV air to the carburetor.l y

On the underside of the rear body section of the carburetor near the front end of the` same is arranged a transfer chamber 22 which has its lower end connected by a passage 23 with the lower part of a Hoat controlled Iliquid fuel supply chamber 24C which receives fuel from any suitable source and delivers the same to the transfer chamber. The lower end of the latter is normally closed by a screw plug 25 which affords access to the chamber and the parts within it for cleaning and inspection.-

Extending across the front part of the mixing' chamber 16 and preferably formed with the rear body section 13 is a vertical post or bridge 26 which is provided with a horizontal longitudinal opening 27 which is axially in line with the rear and front sections of the tubular body. An assembly opening 28 extends vertically from the top to the bottom of the rear body section. through the post 26 and into the upper end of the transfer chamber 22 and intersecting the longitudinal opening 27, as shown in Figs. 1 and 2.

Arranged axially1 within the central part of the rear body section 13 in front of Jthe throttle valve 2O is the casing 29 of a main vaporizer which is preferably of tubular form and provided at its front end with a reducedchoke tube 30 which projects for wardly through the opening 27 in the post' and has a vertical assembly opening 31 which intersects the passage through'the yneck and registerswith the assembly opening 28 in the body and post.

vThe numeral 32 represents Athe tubular fuel nozzle which extends downwardly 'through the assembly opening 28 in the rear body section,V the assembly opening in the l choketube andterminates at its lower end near the bottom of. the transfer chamber. On its central part 'the fuel nozzle is provided With a reduced part which is arranged with the passage of the choke tube and provided with a plurality of jet openings lll leading laterally from the bore of the nozzle to its periphery within the choke tube. Below its jet openings tliefuel n'ozzle is providedl with an external 4screw thread 234 which engages with' an internalscrew thread on theadjacent part/of the choke tube and below its" screw thread the fuel nozzle is provided -with a downwardly facing shoulder 55 hearing against al co-operating. shoulder on the adjacent part of the post 26. Within the bore of the fuel nozzle below its )et openings the same-is providedV with an upwardly facing valve seat 36 toward which a needle valve 13T is relatively movable for controlling the flow of liquid fuel from the. supply through the fuel nozzle. The nee'dle valveis form'ed onl the lower end of a valve Stem 38 whichis arranged with the fuel nozzle and is eonnectednear its upper end with the nozzle by .a screw joint t) so that by turning this stem through the medium of a handle 40 at its upper, end4 the needle valve may vary the size of the passage throughI the nozzle and thus regulate the amountJ of fuel which is supplied to the carburetor for :Vmixture with air to produce the desired combustible mixture for the engine.

Air issupplied to the front or inlet end of the choke tube through a supply conduit having airinner delivery section ll arranged axially within the front section of the body and connected at its inner end by a taper-k ing joint lf2 4with the inlet of the choke tube and an outer receiving sect-ion 43 which may take air from any suitable source but pret erably lfrom ahood il arranged over the exliaiistpipe of the gas engine, .as shown in Fig. (i, sosthat'the air which is supplied to the fuel nozzle will be heated before min- `gling the saine willi the liquid fuel and thereby promote combustion of the mixture and increasing the amount ol' power derived .from the saine.

, During normal running ot' the engine at. high, speed the throttle and choke valves 20 and 2l are wide open whereby the suction of the engine pistons causes the liquid l'uel condition and thereby effects the first dilution ofthe liquid fuel. As this liquid fuel mixed with anvinitial amount of air escapes from the rear end of the vaporizing casing Q9 the same is further mixed willi air which is supplied from the external atmosphere by -dicatc'd at 46 in Fig. 1.

Forl the,purpose of promoting the vaporizatioii of the liquid fuel after the same joins the initial air supplied by the central 'convduit 4l, 43 mainlvaporizing. means are provided which preferably consist of a cellular core which is arranged within the vaporizer casing 29 and which consists of a flat sheet of metal 47 and ay corrugated sheet of metal 48 rolled together and placed in the-casing 29, as shown in Figs. 1, 2 and 3. A plurality of longitudinal Cells or passages 4S) are thus formed within the vaporizer casing upon the surfaces of which the saturated preliminary mixture of liquid fuel and vair is deposited after leaving the fuel nozzle, and choke tube, tlicieby accelerating the vaporization of liquid fuel and effecting an intimate mixture of the saine with the air so that the fuel is finely and evenly distributed throughout tlie air and the combustible quality of the mixture is uniform throughout the entire body of the same, thereby insuring the maximum yield of power from the saine when exploded in the gas engine.

For the purpose of producing a distribution of mixture over all parts of the main vapoiizer a balllc 50 is arranged iu front. of the cellular core so as to cover the central part of the saine. this baille being supported by a rod 5l which is supported on the central part of this vaporizcr core.

lf desired the fuel mixture may be heated as it passes through the main vaporizer within the casing Q9 which can be effected by means of la heating coil 52 surrounding this casing and adapted to be connected with an electric current source such -as 53 which heating means may be used either in connection with or independent'- of the primary heating coil l5 and the, hood 44 overthe exhaust pipe circumstances may require.

lVhen the choke valve .21 is closed the mixtui'e which passes to the engine is very rich inasmuch as the liquid fuel has onl been diluted by the initial air supplied by the central conduit. 4l, 43, which mixture is best suited forstarting the, engine. vAfter the engine has been started the choke valve 2l is opened so that external air enters the body at the rear end of the main vaporizer wherebythe liquid fuel further diluted so that it is lean and in condition for running the engine economically at high speed. h

'and mixes with the partly diluted mixture I .Means are also provided for supplying a mixture of Increased richness to the engine while the throttle is closed and the engine is 1 running lat low speed which means are constructed as follows-:-

The numeral 54 represents a by-pass chamber from which a combustible mixture .1s delivered to the rear part of the rear body section 13 through a by-pass opening 55 which is arranged immediately in rear of the throttle valve 20 in the closedposition of the latter, whereby fuel will be supplied indirectly from the fuel supply nozzle to the engine by the by-pass means during slow speed running instead of directly from the fuel supply nozzle when thethrottle valve is open. Thisby-pass chamber is closed at its top by means of a screw plug 56 and near its top the same has an inlet 57 through whichiliquid fuel taken from the fuel supply nozzle and mixed with .air is introduced. This liquid fuel is conducted by a by-pass pipe 58 which has 'its inlet end connected with the fuel supply nozzle and its outlet end connected with lthe by-pass chamber. The connection between the by-pass pipe and the fuel nozzle is preferably effected by a coupling ring 59 secured to the by-pass pipe and mounted on the upper end of the fuel nozzle between an upwardly facing sho-ulder 60 thereon and a clamping nut 61 having a screw connection therewith, said fuel nozzle having `anannular channel 62 on its periphery within the ring 59 and a plurality of radial openings 63 leading from the .bore of the fuel nozzle to this channel, whereby communication will be constantly maintained between the fuel nozzle and the by-pass pipe regardlessof the relative rotary position of the parts. The connection between the outlet end of the by-pass pipe andthe by-pass `chamber preferably includes a valve mechanism which permits of regulating the iiow of liquid fuel from the fuel nozzle to the bypass chamber. The valve mechanism for this purpose, as shown in the drawings, prefl erably comprises a valve casing 64 having an outlet 65 communicating with the inlet of the by-pass chamber, an inlet 66 connecting with the outlet of the by-pass pipe, a valve seat 67 arranged between theinlet and outlet 66 and outlet 65, and a needle valve 66 having a screw vconnection with the valve casing and movable toward and from the seat 67.

Additional air is supplied to liquid fuel as it enters the by-pass chamber by means of an air by-pass pipe 69 which has its inlet end preferably connected with the outer section 46 of the air supply'pipe while its delivery end is connected with the valve casing 64 and communicates with the outlet 65 A thereof through the medium of a port which ing and movable toward and from a valve seat 71 around said port. l Upon closing the throttle valve for slowing down the engine by reducing the fuel supply the delivery of fuel directly from the nozzle `to the intake manifold will be cut off and instead of liquid fuel escaping from the nozzle through itsI jet openings liquid fuel will bedrawn from the lower end of the nozzle to the top thereof and conducted thence through the fuel by-pass pipe, by-pass chamber and by-pass port to the intake manifold. At the same time added air will be drawn from the nozzle air pipe through the auxiliary air pipe 69 into the by-pass chamber in which latter the fuel and air mix preparatory to entering the intake manifold.

The air for the by-pass is preferably withdrawn from the nozzle air pipe 48 in rearor below the electric heater 45 so that the air will be heated either electrically or byA contact with the exhaust pipe before reaching the intake. This air may however, be heated additionally to or independently of the exhaust pipe and electric heater 45 by means of 'an electric heater 72V arranged in the air by-pass pipe 69 and receiving its electric current supply from the electric'source 46 or elsewhere.

Vaporization of the fuel mixture may also be effected by means of a vapo'rizer in the by-pass chamber consisting preferably of a cellular core formed of a fiat sheet of metal 73 and a corrugated sheet of metal 7 4 vrolled together and forming a plurality of longitudinal cells or passages 75, as shown in Figs. 1 and 3, through which the fuel mixture passes and is rapidly and thoroughly mixed so that'its ingredients are evenly and uniformly distributed throughout the mass and thus promote complete combustion and attain greater efficiency. The fuel is compelled to spread over the entire surface of the vaporizer and thus increase the capacity of the same by employing a baftler 76 which is arranged below .the lower end of the by-pass vaporizer opposite the central part of its core and supported by a rod`77 secured in the center of the respective core, as shown `liquid fuel is drawn from the lower end of the fuel nozzle to the upper end thereof the air supplied by the-nozzle air pipe 41 and 43 instead of passing through the main vaporizer shell 29 is now drawn inwardly through the jet openings 33 into the fuel nozzle where it joins the rising liquid fuel and becomes mixed therewith on its way to the hy-pass pipe and chamber, and intake. It will therefore be noted that when the engine is running at high speed the liquid` :fuel passes outwardly through the jet openings 33 and when the engine is running at low speed the' air passes from the choke tube inwardly through these jet openings.

To in'sure a strong pull on the jet openings from the top 'of the fuel nozzle the upper openings (33 are of greater capacity than the lower jet openings 33, thereby supplying abundant fuel to the engine while running at slow speed. l

By using vaporizers in the manner indicated a greater amount of heated air can be mixed with the fuel and thereby effects a saving in consumption of fuelfor a given output of power. l y n Owing to the increased richness of the mixture when the throttle is closed to slow down the engine and keeping the mixture dry or well distributed by means of the vaporizer in the by-pass chamber carboni zation of the fuel is prevented as well as all engine troubles usually following in the train of carbonization.

I claim as my invention l. A carburetor comprising a tubular body, having a mixture outlet, a main air inlet, a bridge across the interior of said body and provided with an opening, and a fuel chamber arrang'ed in line with said bridge, a choke tube arranged within the opening of said bridge, a fuel nozzle passg ing through said body, bridge and choke vided within said choke tube with jet open- Y`ings and an air supply tube communicating with said choke tube, said fuel nozzle having a screw connection with said choke tube.

2. A. carburetor comprising a tubular body having a. mixture outlet, a main air inlet, a bridge across the interior of said body and provided with an opening, and a 'uel chamber arranged` in linewith said bridge, a choke tube arranged within the opening ot' said bridge, a uelnozzle passing through said body, bridge and choke tube and having the inlet at its lower end arranged within said fuel chamber and pro` vided within said choke tube with jet openings, and an air supply tube communicating with said choke tube, said fuel nozzle having a valve seat, and a needle valve movable toward and from said seat.

3. A fuel preparing device comprisinnY a tubular body having an inlet and an outlet, va throttle valve arranged in the outlet of said body, a fuel nozzle having jet openings in its side which communicate with the interior of said body in front of said throttle valve and provided at its upper end with lateral outlet openings and a shoulder below said openings, acollar surrounding said outlet openings, a screw nut on said nozzle engaging said collar, and means for conducting fuel from said nozzle to said body in front of the throttle valve including a pipe F which connects with said collar.

FRANCIS G. CRONE. 

